چکیده انگلیسی

Abstract
Axis I comorbidity is associated with greater severity of social anxiety disorder. However, the differential effects of comorbid mood and anxiety disorders on symptom severity or treatment outcome have not been investigated. We evaluated 69 persons with uncomplicated social anxiety disorder, 39 persons with an additional anxiety disorder, and 33 persons with an additional mood disorder (with or without additional anxiety disorders). Those with comorbid mood disorders reported greater duration of social anxiety than those with uncomplicated social anxiety disorder. They were also judged, before and after 12 weeks of cognitive-behavioral group treatment and at follow-up, to be more severely impaired than those with no comorbid diagnosis. In contrast, persons with comorbid anxiety disorders were rated as more impaired than those with no comorbid diagnosis on only a single measure. Type of comorbid diagnosis did not result in differential rates of improvement of social anxiety disorder.

نتیجه گیری انگلیسی

Results
3.1. Sample characteristics
In the SAD/A group (n=39), generalized anxiety disorder (GAD; 53.85%) was the most common additional diagnosis, followed by specific phobia (28.21%), panic disorder with agoraphobia (12.82%), and anxiety disorder not otherwise specified (17.95%). The least commonly reported additional anxiety disorders included agoraphobia without a history of panic disorder (2.56%), obsessive compulsive disorder (2.56%), and post-traumatic stress disorder (7.69%). Among those in the SAD/D group (n=33), over one-half were assigned an additional diagnosis of major depressive disorder (54.55%); 27.27% were diagnosed with dysthymic disorder; 27.27% received a diagnosis of depressive disorder NOS. As previously described, those in the SAD/D group were permitted to have additional anxiety disorders. Forty-six percent of those in the SAD/D group had no additional anxiety disorder; 33% had one additional anxiety disorder; 21% had two additional anxiety disorders. Again, the most frequently reported additional anxiety disorders for those in the SAD/D group were GAD (36.36%) and specific phobia (21.21%). In the SAD/D group, those patients with additional anxiety disorders did not differ from those without an additional anxiety disorder on independent assessor ratings [Wilks' λ=0.82; F(3,29)=2.11;ns], self-report measures [Wilks' λ=0.89; F(4,22)=0.69; ns], or behavior test measures [Wilks' λ=0.79; F(4,28)=1.84; ns].
3.2. Demographic characteristics of the study sample
Comparisons on categorical (i.e., sex, marital status, education, employment status) and continuous (i.e., age, annual income) demographic variables were made using chi-square analyses and one-way analyses of variance (ANOVAs), respectively. Of the total sample, 48% were female, 38% were married, 73% had completed college, and 78% were employed. Their average age was 36.48 (SD=9.63). The groups differed only with regard to annual income, F(2,138)=3.91, P<0.05. Tukey HSD post hoc tests revealed that patients in the SAD/D group earned a lower mean annual income (M=$19,226; SD=$14,843) than did those in the SAD group (M=$35,537; SD=$34,454). The SAD/A group (M=$29,211; SD=$17,736) did not differ from the other groups on this measure.
3.3. Pretreatment clinical characteristics of the study sample
The three groups were compared on clinical variables using one-way ANOVAs and Tukey HSD tests. The groups differed with regard to current and past year global assessment of functioning (GAF) and age of onset of social anxiety disorder, but not duration of social anxiety disorder. Patients in the SAD/D group reported an earlier age of onset of social anxiety disorder and received lower mean past year GAF ratings than did patients in either of the other two groups, which did not differ from each other on these measures [age of onset: SAD/D, M=13.13, SD=7.66; SAD/A, M=18.62, SD=10.11; SAD, M=18.06, SD=9.94; F(2,138)=3.62, P<0.05; past year GAF: SAD/D, M=59.27, SD=8.77; SAD/A, M=65.32, SD=9.47; SAD, M=69.58, SD=8.79; F(2,138)=14.70, P<0.001]. The SAD/D group also received lower mean current GAF ratings (M=56.73; SD=9.21) than did the SAD/A group (M=63.97; SD=8.71), which was assigned lower mean ratings than the SAD group (M=68.19; SD=8.67), F(2,138)=18.76, P<0.001.
3.4. Pretreatment assessment of the severity of social anxiety disorder symptoms
Three one-way multivariate analyses of variance (MANOVAs), with comorbidity group as the independent variable, were conducted for pretreatment independent assessor ratings, scores on self-report questionnaires, and behavior test ratings, respectively. The MANOVA for the independent assessment measures [Wilks' λ=0.88; F(6,268)=2.97; P<0.01] yielded a significant effect for comorbidity group. The MANOVAs for the behavior test ratings [Wilks' λ=0.98; F(8,264)=0.41; ns] and the self-report indices [Wilks' λ=0.88; F(8,232)=1.96; P=0.052] were not significant, although the analysis for the self-report measures fell just short. To clarify the results of the MANOVA, significant results were followed by one-way ANOVAs, which were followed by Tukey HSD post hoc comparisons (see Table 1). For all independent assessment measures, the SAD/D group was rated as more impaired than the SAD group. The SAD/A group differed from neither the SAD/D group nor the SAD group.
Table 1.
Comparison of participants with uncomplicated Social anxiety Disorder (SAD). Social Anxiety Disorder with a Comorbid Anxiety Disorder (SAD/A), and Social Anxiety Disorder with a Comorbid Depressive Disorder (SAD/D) on pretreatment measures of Social Anxiety Disorder symptom severitya
SAD SAD/A SAD/D F
n=69 n=39 n=39
M SD M SD M SD
Independent assessor
Clinician Severity Rating 5.56b 1.00 5.82bc 1.04 6.15c 0.94 4.00*
LSAS: social fear 14.50b 6.85 16.92bc 6.22 19.79c 6.43 7.32**
LSAS: performance fear 15.91b 4.73 17.53bc 5.75 20.39c 6.45 7.50**
a
N=141. Means in the same row that do not share the same superscript differ at P<0.05 in the Tukey HSD post hoc comparison. Clinician Severity Rating=Anxiety Disorders Interview Schedule Clinican Severity Rating, LSAS=Liebowitz Social Anxiety Scale. *P<0.05; **P<0.001.
Table options
3.5. Analysis of posttreatment outcome
Of the 141 original participants, 118 participated in the CBGT protocol described above. The remaining patients either received non-cognitive-behavioral treatment in the study of Heimberg and colleagues (1998) or did not receive treatment at the Center for Stress and Anxiety Disorders. Ten patients in the SAD group (16.7%), four in the SAD/A group (12.5%), and four in the SAD/D group (15.4%) discontinued treatment before the posttreatment assessment was completed, a nonsignificant difference (χ2[2,N=118]=2.81, ns). There were no pretreatment differences between those who dropped out and those who did not on any of the outcome measures [independent assessment ratings: Wilks' λ=0.98; F(3,111)=0.86; ns; self-report measures: Wilks' λ=0.99; F(4,94)=0.14; ns; behavior test ratings: Wilks' λ=0.99; F(4,111)=0.31; ns]. Because data were missing for some measures, sample sizes vary slightly in these and the following analyses.
Three repeated measures 3 (comorbidity group) by 2 (time: pre- to post-treatment) MANOVAs were conducted on the three categories of outcome measures (see Table 2). Multivariate analysis of the independent assessor ratings revealed significant main effects of time [Wilks' λ=0.37; F(3,88)=49.99; P<0.001] and comorbidity group [Wilks' λ=0.86; F(6,176)=2.24; P<0.05]. The group by time interaction was not significant [Wilks' λ=0.96; F(6,176)=0.61; ns]. The univariate time effects were significant for all measures. The significant multivariate group effect reflects the pattern that those in the SAD/D group were rated as more severe than those in the SAD group on the ADIS clinician's severity rating and the LSAS Performance Fear subscale both before and after treatment, while this was not the case for the SAD/A group.
Table 2.
Comparison of participants with uncomplicated Social Anxiety Disorder (SAD), Social Anxiety Disorder with a Comorbid Anxiety Disorder (SAD/A), and Social Anxiety Disorder with a Comorbid Depressive Disorder (SAD/D) on pre- and post-treatment measures of symptom severitya
Pretreatment Posttreatment F
SAD SAD/A SAD/D SAD SAD/A SAD/D Time Group
n=50 n=28 n=22 n=50 n=28 n=22
M SD M SD M SD M SD M SD M SD
Independent assessor
ADIS CSR 5.95 0.96 6.04 0.95 6.04 0.88 3.91 1.31 4.42 1.18 4.65 1.19 143.36** 3.99*
LSAS: Social fear 15.39 6.88 16.42 6.45 18.87 7.10 12.50 6.38 12.54 6.13 15.83 6.31 48.23** 2.39
LSAS: Performance fear 15.98 4.91 17.71 4.76 19.65 5.62 12.74 4.95 14.67 5.01 16.09 5.98 64.74** 4.28*
Self-report
FQ: social 18.21 7.20 20.89 6.82 20.44 8.50 14.08 6.84 16.17 6.48 15.69 8.68 31.65** —
FNE 22.42 7.35 22.50 6.18 25.06 7.14 20.24 7.18 21.39 7.63 24.25 6.89 2.86 —
SPS 28.29 13.01 31.44 19.58 31.19 16.12 20.92 11.66 23.89 13.73 20.31 11.47 37.40** —
SIAS 42.11 16.07 40.89 16.47 49.19 12.99 34.68 15.95 34.06 15.24 40.12 8.24 37.19** —
Behavior test
Performance quality 46.34 23.10 48.04 26.57 44.71 21.47 69.88 21.05 63.91 22.31 60.59 22.97 27.49** —
Maximum anxiety 66.59 22.95 74.35 21.65 73.53 21.71 53.78 17.46 51.30 17.92 57.06 17.14 40.24** —
Anticipatory SUDS 36.63 20.35 46.04 23.15 41.82 20.81 45.24 17.96 41.46 16.84 51.31 19.39 2.65 —
Performance SUDS 54.05 24.72 62.02 22.71 59.52 21.67 42.35 15.05 38.70 13.99 49.07 16.34 34.93** —
Self-reported depression
BDI 7.74 5.67 11.32 8.58 19.05 8.73 5.93 5.43 7.59 6.84 12.35 7.82 — —
a
N=100. ADIS CSR=Anxiety Disorders Interview Schedule Clinician Severity Rating, LSAS=Liebowitz Social Anxiety Scale, FQ: social=social phobia subscale of the Fear Questionnaire, FNE=Fear of Negative Evaluation Scale, SPS=Social Phobia Scale, SIAS=Social Interaction Anxiety Scale, SUDS=Subjective Units Of Discomfort Scale, BDI=Beck Depression Inventory. Dashes indicate that univariate effects were not examined because the multivariate effect was not significant. The univariate group X \???\ time interaction was significant for the BDI, F(2, 85)=4.27, p<.05. No other univariate interaction effects were examined because the multivariate interaction effect failed to achieve significance. *P<0.05; **P<0.001.
Table options
Analysis of scores on the self-report measures revealed a significant main effect of time [Wilks' λ=0.55; F(4,66)=13.68; P<0.001]. However, neither the main effect of comorbidity group [Wilks' λ=0.87; F(8,132)=1.15; ns] nor the group by time interaction [Wilks' λ=0.96; F(8,132)=0.38; ns] was significant. Univariate ANOVAs revealed that the time effects were significant for the FQ: social, the SPS, and the SIAS, but not FNE.
Analysis of the behavior test ratings revealed a significant main effect of time [Wilks' λ=0.47; F(4,75)=21.27; P<0.001]. However, neither the main effect of comorbidity group [Wilks' λ=0.96; F(8,150)=0.34; ns] nor the group by time interaction [Wilks' λ=0.86; F(8,150)=1.47; ns] was significant. Univariate ANOVAs revealed that the time effects were significant for the performance quality, maximum anxiety, and mean SUDS ratings reported during the behavior test, but not for mean anticipatory SUDS ratings.
3.6. Analyses of follow-up outcome
Patients who completed treatment and did not subsequently participate in additional treatment or maintenance sessions as part of the Heimberg et al. (1998) study were invited to participate in 6- and 12-month follow-up assessments. For the purpose of the present study, 12-month follow-up data were used when available (n=46); 6-month data were substituted in the event of missing 12-month data n=6). Of the 83 participants who completed treatment and qualified for follow-up assessment, 52 patients were included in the current analyses. Thirteen patients in the SAD group (34.2%), eleven in the SAD/A group (40.7%), and seven in the SAD/D group (38.9%) discontinued their participation in the study before either follow-up assessment could be completed, a nonsignificant difference (χ2[2,N=83]=0.31, ns). There were no pretreatment differences between those who completed follow-up assessment and those who did not on any of the outcome measures [independent assessment ratings: Wilks' λ=0.91; F(3,77)=2.68; ns; self-report measures: Wilks' λ=0.89; F(4,64)=2.00; ns; behavior test ratings: Wilks' λ=0.97; F(4,76)=0.54; ns]. Additionally, there were no posttreatment differences between those who completed follow-up assessment and those who did not on any of the outcome measures [independent assessment ratings: Wilks' λ=0.94; F(3,72)=1.57; ns; self-report measures: Wilks' λ=0.98; F(4,52)=0.24; ns; behavior test ratings: Wilks' λ=0.94; F(4,64)=1.10; ns].
Three repeated measures 3 (comorbidity group) by 2 (time: pretreatment to follow-up) MANOVAs were conducted on the three categories of outcome measures (see Table 3). Multivariate analysis of the independent assessor ratings revealed significant main effects of time [Wilks' λ=0.30; F(3,43)=33.17; P<0.001] and comorbidity group [Wilks'λ=0.73; F(6,86)=2.44; P<0.05]. The group by time interaction was not significant [Wilks' λ=0.81; F(6,86)=1.58; ns]. Univariate ANOVAs revealed that the time effects were significant for all measures. The significant multivariate group effect reflects the pattern that those in the SAD/A group were rated as more severe than those in the SAD group on the LSAS Performance Fear subscale both before and after treatment, while this was not the case for the SAD/D group.
Table 3.
Comparison of participants with uncomplicated Social Anxiety Disorder (SAD). Social Anxiety Disorder with a Comorbid Anxiety Disorder (SAD/A), and Social Anxiety Disorder with a Comorbid Depressive Disorder (SAD/D) on pretreatment and follow-up measures of symptom severitya
Pretreatment Follow-up F
SAD SAD/A SAD/D SAD SAD/A SAD/D Time Group
n=25 n=16 n=11 n=25 n=16 n=11
M SD M SD M SD M SD M SD M SD
Independent assessor
ADIS CSR 5.57 0.98 6.25 0.77 6.09 0.70 3.05 1.63 3.56 1.90 4.36 1.50 99.00** 2.88
LSAS: Social fear 16.19 6.52 16.19 6.82 16.45 7.20 10.76 6.66 13.25 6.93 14.09 6.73 23.42** 0.35
LSAS: Performance fear 15.10 4.84 17.88 4.50 16.00 5.02 10.48 4.68 15.81 6.43 14.82 5.60 17.80** 3.50*
Self-report
FQ: social 17.59 6.81 18.67 7.08 18.36 8.59 13.09 7.12 15.60 5.63 16.55 9.47 17.18** —
FNE 25.05 5.52 21.33 7.71 23.45 8.19 21.41 7.41 19.93 9.92 21.18 9.68 6.13* —
SPS 27.36 12.04 32.00 19.94 27.36 15.09 18.32 10.88 23.60 14.89 17.45 15.23 29.01** —
SIAS 45.45 15.83 39.60 15.69 47.09 14.00 35.64 15.51 31.73 12.71 41.36 14.97 19.38** —
Behavior test
Performance quality 47.27 19.80 51.25 26.30 41.00 14.30 66.82 16.15 67.81 24.96 59.00 21.32 17.06** —
Maximum anxiety 69.55 20.81 76.88 19.82 61.00 18.97 50.68 24.12 51.25 19.87 52.50 21.76 23.56** —
Anticipatory SUDS 38.80 23.53 48.17 24.02 35.33 20.12 34.85 18.09 40.83 19.38 43.10 27.90 0.08 —
Performance SUDS 58.33 25.09 65.21 19.19 48.80 18.56 38.05 19.20 40.13 19.58 42.60 23.81 27.41** —
Self-reported depression
BDI 8.71 6.08 9.94 9.24 20.50 9.68 7.33 7.29 6.75 6.13 11.20 8.28 — —
a
N=52. ADIS CSR=Anxiety Disorders Interview Schedule Clinician Severity Rating, LSAS=Liebowitz Social Anxiety Scale, FQ: social=social phobia subscale of the Fear Questionnaire, FNE=Fear of Negative Evaluation Scale, SPS=Social Phobia Scale, SIAS=Social Interaction Anxiety Scale, SUDS=Subjective Units Of Discomfort Scale, BDI=Beck Depression Inventory. Dashes indicate that univariate effects were not examined because the multivariate effect was not significant. The univariate group X\???\ time interaction was significant for the BDI, 1(2, 47)=4.31, p<.05. No other univariate interaction effects were examined because the multivariate interaction effect failed to achieve significance. *P<0.05; **P<0.001.
Table options
Analysis of scores on the self-report measures revealed a significant main effect of time [Wilks' λ=0.57; F(4,42)=7.91; P<0.001]. However, neither the main effect of comorbidity group [Wilks' λ=0.73; F(8,84)=1.77; ns] nor the group by time interaction [Wilks' λ=0.88; F(8,84)=0.73; ns] was significant. Univariate ANOVAs revealed that the time effects were significant for all measures.
Analysis of the behavior test ratings demonstrated that there was a significant main effect of time [Wilks' λ=0.51; F(4,42)=10.19; P<0.001]. However, neither the main effect of comorbidity group [Wilks' λ=0.88; F(8,84)=0.69; ns] nor the group by time interaction [Wilks' λ=0.88; F(8,84)=0.69; ns] was significant. Univariate ANOVAs revealed that the time effects were significant for the performance quality, maximum anxiety, and mean SUDS ratings reported during the behavior test, but not for mean anticipatory SUDS ratings.
3.7. Assessment of the severity of depressive symptoms over time
Groups differed from each other on pretreatment depression F(2,134)=22.37, P<0.001]. The SAD/D group rated itself more depressed (M=19.00; SD=9.01) than the SAD/A group (M=13.26; SD=8.80), which rated itself more depressed than the SAD group (M=8.26; SD=5.81). A repeated measures 3 (comorbidity group) by 2 (time: pre- to post-treatment) ANOVA was conducted on BDI scores and revealed a significant group by time interaction [F(2,85)=4.27; P<0.05] (see Table 2). Paired sample t-tests were conducted for each of the three comorbidity groups to examine simple main effects of time. Significant simple main effects of time were evidenced for the SAD/D [t(19)=3.61; P<0.05], the SAD/A [t(21)=2.77; P<0.05], and the SAD [t(45)=2.36; P<0.05] groups, indicating improvement in depression. One-way ANOVAs were conducted separately for pre- and post-treatment assessments to examine simple main effects of group. Group differences were noted at pretreatment [F(2,95)=16.15; P<0.001]; the SAD/D group rated itself more depressed than the other two groups, which did not differ. Group differences were still in evidence at posttreatment [F(2,86)=7.37; P<0.001]; the SAD/D group rated itself more depressed than the SAD group. The SAD/A group differed from neither of the other two groups.
Similarly, a repeated measures 3 (comorbidity group) by 2 (time: pretreatment to follow-up) ANOVA was conducted on BDI scores and revealed a group by time interaction [F(2,47)=4.31; P<0.05] (see Table 3). Paired sample t-tests were conducted for each of the three comorbidity groups to examine simple main effects of time. Significant reduction in depression was noted for the SAD/D group [t(9)=2.76; P<0.05], but not for either the SAD/A [t(15)=1.66; ns] or SAD [t(23)=1.41; ns] groups. One-way ANOVAs were conducted separately for pre- and follow-up assessments to examine simple main effects of group. Group differences were evidenced at pretreatment [F(2,49)=7.56; P<0.001] such that the SAD/D group rated itself more depressed than the other two groups, which did not differ. No group differences in depression were noted at the 12-month follow-up.